1. Technical Field
The present invention relates to a locking washer for preventing construction elements fastened by a fastener from being loosened, and a locking apparatus using such a washer.
2. Related Art
A construction generally includes construction elements thereof fastened to one another by fasteners. For instance, a wooden building includes a pillar fixed to a beam by means of a fastener such as a strap bolt. In fastening a pillar to a beam with use of a strap bolt, a base plate of the strap bolt is fixed to the beam, and a bolt portion of the strap bolt is inserted through a through hole formed in the pillar. Then, a nut attached to the bolt portion of the strap bolt is tightened to thereby fix the pillar to the beam.
Although a wooden building is preferably constructed by use of fully dried wood, construction costs impractically increases in this case. On the other hand, in a wooden building constructed by use of insufficiently dried wood, such wood will be thinned with elapse of time. If, for instance, a pillar becomes thinned, the fastening of the pillar and the beam by a bolt/nut fastener is loosened. As a consequence, a problem is posed that the loosened pillar may vibrate when it receives external vibration caused by earthquake, vehicle traffic or the like.
The same is applied to other constructions, such as bridge, railroad rail, vehicular load-carrying platform, comprised of rigid construction elements fastened by fasteners. That is, if these constructions are frequently subject to vibration for a long time, the fastening of construction elements becomes loosened, so that the constructions are liable to vibrate.